Water jet propulsion watercraft

ABSTRACT

A water jet propulsion watercraft includes a hull, a cockpit arranged at a hull center and including a periphery that is surrounded by a wall surface, a rear deck arranged at a hull rear portion at a rear of the cockpit and including a rear water-access area that is open to the rear, a saddle type watercraft operator seat arranged in the cockpit, a jet propulsion device attached to the hull and arranged to apply a propulsive force to the hull by sucking in water from surroundings and jetting the water, and an engine attached to the hull and arranged to apply a driving force to the jet propulsion device. The saddle type watercraft operator seat may extend in a front/rear direction of the hull and be arranged to divide an interior of the cockpit into two regions at the right and left.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a water jet propulsion watercraft which includes a hull, and a jet propulsion device arranged to apply a propulsive force to the hull.

2. Description of the Related Art

A water jet propulsion watercraft according to a prior art is disclosed in Japanese Unexamined Patent Application Publication No. H07-277274. This water jet propulsion watercraft belongs to a category of personal watercrafts (PWCs). That is, this water jet propulsion watercraft includes a tandem seat, on which an occupant sits in a straddle orientation, and a steering handle disposed in front of the tandem seat. A flat portion is provided at a stern side of the hull and this facilitates boarding and exiting from the stern side. Foot placement areas provided under the feet of the occupant communicate with the flat portion via drainage grooves. Seawater is thereby prevented from being retained under the feet of the occupant and efficiency of drainage during washing is also improved.

SUMMARY OF THE INVENTION

The inventors of preferred embodiments of the present invention described and claimed in the present application conducted an extensive study and research regarding a water jet propulsion watercraft, such as the one described above, and in doing so, discovered and first recognized new unique challenges and previously unrecognized possibilities for improvements as described in greater detail below.

A personal watercraft is designed based on the premise that the occupant gets wet with water. That is, the design is premised on the fact that water enters into the foot placement areas provided for the occupant from the flat portion provided for boarding and exiting from and into the water. Thus, if a user does not want to get wet with water, the personal watercraft is not suitable for use.

Jet boats (which may also be referred to at times as “pleasure boats” or “sports boats”) are another category of water jet propulsion watercrafts. A jet boat includes a well, an entire periphery of which is surrounded by a wall surface, and a watercraft operator seat and a passenger seat are provided inside the well. The watercraft operator seat is a seat that can be sat on with the operator's legs closed (e.g., a non-straddle orientation). An interior of the well is a dry area into which water does not enter from the surroundings. The jet boat is thus an appropriate choice for a user who does not want to get wet with water. On the other hand, access to and from the water in the surroundings of the hull is not as easy as in the case of a personal watercraft, and thus the jet boat is not necessarily suitable for an application premised on boarding and exiting between the hull and the water. Moreover, the jet boat is generally large and thus cannot be used casually, and also has a problem of being high in maintenance and operation cost because a large space is required for mooring.

For example, in a case where some of a plurality of occupants desire to board and exit between the hull and the water while the others dislike getting wet with water, a jet boat is presumably selected. However, a jet boat is generally premised on transporting a comparatively large number of occupants, and thus it cannot be used as casually as a personal watercraft. Thus, in a case where preferences are divided among a small number of occupants, neither a personal watercraft nor a jet boat is suitable for use. Thus, in such a case, a water jet propulsion watercraft cannot provide an appropriate choice.

In order to overcome the previously unrecognized and unsolved challenges described above, a preferred embodiment of the present invention provides a water jet propulsion watercraft including a hull, a cockpit arranged at a hull center and including a periphery that is surrounded by a wall surface, a rear deck disposed at a hull rear portion to a rear of the cockpit and including a rear water-access area that is open to the rear, a saddle type watercraft operator seat arranged in the cockpit, a jet propulsion device attached to the hull and arranged to apply a propulsive force to the hull by sucking in water from surroundings and jetting the water, and an engine attached to the hull and arranged to apply a driving force to the jet propulsion device.

By this arrangement, the cockpit includes an entire periphery that is surrounded by the wall surface and thus provides a dry area into which water in the surroundings of the hull does not enter readily. The rear deck disposed at the hull rear portion includes the water-access area that is open to the rear, and thus enables exiting into water and boarding from the water to be performed readily. The saddle type watercraft operator seat is disposed at the cockpit preferably located at the hull center, and the hull can thus be arranged compactly. A new category can thus provided for a water jet propulsion watercraft that obtains a propulsive force from a jet propulsion device driven by an engine (which may be an internal combustion engine). In other words, a water jet propulsion watercraft can be provided in which a dry area and a water-access area can both be included in a compact hull and which can thus be used casually and yet can accommodate and satisfy the diverse needs of occupants.

Preferably, the rear deck includes a floor surface that is sloped so as to descend toward the rear. By this arrangement, even if the rear deck is contacted by and washed over with waves, the water can be drained readily from the rear water-access area due to the rearwardly sloping floor surface.

Preferably, the saddle type watercraft operator seat extends in a front/rear direction of the hull and divides an interior of the cockpit into two regions at the right and left. By this arrangement, the saddle type watercraft operator seat can be disposed at a center in regard to a right/left direction. Balance can thereby be achieved readily even with a small-scale hull. Also, the two regions are secured at the right and left of the saddle type watercraft operator seat, and thus accommodation spaces for the occupants can be provided at both the right side and the left side of the hull. The right and left accommodation spaces can be used, for example, for fishing. That is, fishing and other activities can be performed at both the right and the left sides of the hull.

The saddle type watercraft operator seat does not have to be of a structure that completely partitions the cockpit into the right and left.

Preferably, the water jet propulsion watercraft further includes a first passenger seat arranged inside the cockpit and at the rear of the saddle type watercraft operator seat, and the engine is disposed below the first passenger seat. By this arrangement, the hull can be made short because the first passenger seat is provided at the rear of the saddle type watercraft operator seat and the engine is arranged by making use of space below the first passenger seat. In particular, the first passenger seat is preferably a saddle type seat that is continuous with the rear of the saddle type watercraft operator seat, and installation space for the engine can thereby be secured readily.

The first passenger seat may be designed to enable seating of a single occupant or may be designed to enable seating of two or more occupants. Also, the saddle type watercraft operator seat and the first passenger seat may be made continuous in the front/rear direction to form a tandem seat. The interior of the cockpit may be divided into the right and left regions by such a tandem seat.

Preferably, the water jet propulsion watercraft further includes a second passenger seat provided inside the cockpit and at the right side of the first passenger seat, and a third passenger seat arranged inside the cockpit and at the left side of the first passenger seat. By this arrangement, a center of gravity of an entirety of the hull including the occupants can be disposed at a vicinity of the engine because the second and third passenger seats are disposed at the right and left of the first passenger seat. Shortening of hull length by disposing of the engine in a space below the first passenger seat can thereby be achieved while at the same time disposing the center of gravity at the rear. Consequently, a contribution can be made toward establishing motion performance (in particular, turning performance) of the hull. That is, if the hull length is shortened in a case where the engine is disposed in front of the jet propulsion device, it becomes difficult to dispose the center of gravity at the rear. Thus, by disposing the engine by making use of the space below the first passenger seat and further disposing the second and third passenger seats to the right and left thereof, concentrating of the center of gravity is realized. Shortening of the hull length and rearward disposing of the center of gravity, which are in a mutually conflicting relationship, can thereby be realized at the same time.

Preferably, the water jet propulsion watercraft preferably further includes a fourth passenger seat arranged at the rear deck. By this arrangement, fishing and other activities can be performed at the rear of the hull because the fourth passenger seat is provided at the rear deck. The rear deck is mainly used suitably during mooring and low speed movement (for example, during trolling) because it has the water-access area that is opened to the rear.

The fourth passenger seat is preferably arranged so as to be adjacent to the first passenger seat at the rear of the first passenger seat. A further contribution can thereby be made to establishing the motion performance of the hull because concentrating of the center of gravity near the engine can be achieved.

The fourth passenger seat preferably has a seat that faces the rear of the hull. An occupant seated at the fourth passenger seat can thereby stick out a fishing rod toward the rear.

The rear deck preferably includes a footrest arranged to enable an occupant, seated at the fourth passenger seat, to place his/her feet thereon. The footrest is preferably formed so as to rise from a hull rear edge. The occupant at the fourth passenger seat can place his/her feet on the footrest for comfort.

Preferably, the cockpit is defined by right and left side walls, storage spaces are provided in the right and left side walls, and spaces to the right and left of the saddle type watercraft operator seat are narrowed by the storage spaces. By this arrangement, the spaces to the right and left of the saddle type watercraft operator seat are narrowed by the provision of the storage spaces in the right and left side walls. Movement ranges of the occupants can thereby be restricted appropriately and stabilization of the hull can be achieved. At the same time, the storage spaces can be secured.

Preferably, the water jet propulsion watercraft further includes a front deck arranged at a hull front portion in front of the cockpit and having a front water-access area that is opened to the front. By this arrangement, the front deck at the hull front portion includes the water-access area that is open to the front, thus enabling access into water from the hull front portion and boarding onto the hull front portion from the water. An activity space for fishing or other activity can thereby be provided at the front side of the hull as well.

Preferably, the water jet propulsion watercraft preferably further includes a fifth passenger seat arranged at the front deck. By this arrangement, fishing and other activities can be performed readily at the front of the hull because the fifth passenger seat is provided at the front deck. The front deck is mainly used suitably during mooring and low speed movement (for example, during trolling) because it includes the water-access area that is opened to the front. The fifth passenger seat is preferably disposed, for example, so that a hull center line passes therethrough in plan view. The fifth passenger seat can thereby be disposed without compromising the balance of the hull.

Preferably, the water jet propulsion watercraft preferably further includes a seat attachment portion arranged at the front deck and arranged to enable attachment and detachment of the fifth passenger seat. By this arrangement, the fifth passenger seat can be attached when necessary, and the fifth passenger seat can be removed when it is unnecessary. For example, when the water jet propulsion watercraft is to travel at high speed, the fifth passenger seat is preferably removed to reduce air resistance and secure a wider field of view for a watercraft operator. Also, when fishing or other activity is to be performed or during low speed travel (for example, during trolling), the fifth passenger seat is preferably attached to the seat attachment portion to facilitate the activity at the front deck.

Preferably, the water jet propulsion watercraft further includes a storage portion arranged at the front deck and arranged to be capable of housing the fifth passenger seat that is attachable to the seat attachment portion. By this arrangement, the fifth passenger seat that is detachable can be stored in the storage portion of the front deck. Transport of the fifth passenger seat is thereby facilitated. Especially, when the water jet propulsion watercraft is to travel at high speed, the fifth passenger seat is preferably housed in the storage portion to secure a wider field of view for the watercraft operator and reduce the air resistance. The seat attachment portion may be provided at a lid of the storage portion.

Preferably, the water jet propulsion watercraft further includes a footrest being for a user seated at the fifth passenger seat and formed to a shape that rises from a hull edge portion at the front deck. By this arrangement, the footrest is formed so as to rise from a hull edge portion at the front deck, so that the occupant seated at the fifth passenger seat can place his/her feet on the footrest for comfort.

Preferably, the front deck includes a floor surface that is sloped so as to descend toward the front. By this arrangement, even if the front deck is contacted by and washed with waves, the water can be drained readily from the front water-access area due to the forwardly sloping floor surface.

Preferably, the water jet propulsion watercraft preferably further includes an arch-shaped towing tower erected from right and left edge portions of the hull near a boundary portion between the cockpit and the rear deck. By this arrangement, towing can be performed using the towing tower. Specifically, a rope for towing a water skier, etc., can be coupled to the towing tower. The towing tower preferably has the arch shape and can thus be disposed without compromising occupant comfort of the cockpit, etc. Also, the towing tower is disposed near the boundary portion between the cockpit and the rear deck and thus contributes to the rearward disposing of the center of gravity of the hull. A contribution can thus be made to establishing the motion performance of the hull.

Other elements, features, steps, characteristics and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiments with reference to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is perspective view of a water jet propulsion watercraft according to a preferred embodiment of the present invention.

FIG. 2 is a plan view of the water jet propulsion watercraft.

FIG. 3 is a front view of the water jet propulsion watercraft.

FIG. 4 is a left side view of the water jet propulsion watercraft.

FIG. 5 is a rear view of the water jet propulsion watercraft.

FIG. 6A is an enlarged perspective view of an arrangement of a front deck and shows a state where a fifth passenger seat is removed.

FIG. 6B is an enlarged perspective view of the arrangement of the front deck and shows a state where the fifth passenger seat is attached.

FIG. 6C is an enlarged perspective view of the arrangement of the front deck and shows a state where the fifth passenger seat is housed.

FIG. 7 is a schematic side view of an arrangement of an interior of a hull of the water jet propulsion watercraft.

FIG. 8 is a schematic plan view of the arrangement of the interior of the hull.

FIG. 9 is a schematic sectional view for explaining an arrangement example of a jet propulsion device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 is perspective view of a water jet propulsion watercraft according to a preferred embodiment of the present invention. The water jet propulsion watercraft 1 includes, a hull 2, a cockpit 3 arranged at a hull center, a rear deck 4 arranged at a rear of the cockpit 3, a front deck 5 arranged in front of the cockpit 3, and an arch-shaped towing tower 6.

The hull 2 is arranged by joining together a hull body 2 a and a deck portion 2 b by a gunwale 7. The cockpit 3 is arranged at a central region of the deck portion 2 b. The rear deck 4 is arranged at a rear region of the deck portion 2 b. The front deck 5 is arranged at a front region of the deck portion 2 b. The towing tower 6 is arranged between the cockpit 3 and the rear deck 4.

FIG. 2 is a plan view of the water jet propulsion watercraft 1, FIG. 3 is a front view thereof, FIG. 4 is a left side view thereof, and FIG. 5 is a rear view thereof.

The cockpit 3 defines a well 11, an entire periphery of which is surrounded by a wall surface 10. A tandem seat 12 extending in a front/rear direction is arranged at a central portion of the cockpit 3. The tandem seat 12 is a saddle type seat on which occupants sit in a straddle orientation. The tandem seat 12 includes a watercraft operator seat 13 and a first passenger seat 21 that are joined in the front/rear direction. The watercraft operator seat 13 (saddle type watercraft operator seat) is arranged at a front portion, and the first passenger seat 21 is arranged at a rear portion. Thus, the watercraft operator seat 13 and the first passenger seat 21 are both saddle type seats. The first passenger seat 21 preferably has a length such that two occupants can be seated next to each other at the front and rear.

The tandem seat 12 is disposed along a center line C of the hull 2 in plan view and a rear end portion thereof is coupled to a rear partition wall 15 that partitions the cockpit 3 and the rear deck 4. The rear partition wall 15 rises upward from the rear end portion of the tandem seat 12 and is arranged to hold a waist portion of an occupant on the first passenger seat 21. The rear partition wall 15 extends to the right and left from the rear end portion of the tandem seat 12 and furthermore curves forward and is coupled to right and left side walls 16R and 16L of the deck portion 2 b. The rear partition wall 15 is formed higher than the right and left side walls 16R and 16L.

A steering handle 30 operated by a watercraft operator seated at the watercraft operator seat 13 is arranged in front of the tandem seat 12. The steering handle 30 preferably is a bar handle and includes a right grip 31R and a left grip 31L that are arranged to be held by right and left hands of the watercraft operator. An instrument case 32 is arranged between the grips 31R and 31L. The steering handle 30 is provided in a manner enabling right and left turning about a turning axis passing through a vicinity of the instrument case 32.

A handle holding portion 33 is arranged to hold the steering handle 30. The handle holding portion 33 is arranged a step higher than the tandem seat 12. A pair of front partition walls 18R and 18L that extend to the right and left are provided at the right and left of the handle holding portion 33. Outer edges of the front partition walls 18R and 18L are coupled respectively to the side walls 16R and 16L. The front partition walls 18L and 18R are arranged higher than the side walls 16R and 16L and have curved shapes that are forwardly convex in plan view.

An interior of the cockpit 3 is divided into a right region 3R and a left region 3L by the tandem seat 12. The left region 3L is defined by the tandem seat 12, the rear partition wall 15, the left side wall 16L, and the left front partition wall 18L and defines a left well 11L, an entire periphery of which is surrounded by wall surfaces of the walls. The right region 3R is defined by the tandem seat 12, the rear partition wall 15, the right side wall 16R, and the right front partition wall 18R and defines a right well 11R, an entire periphery of which is surrounded by wall surfaces of the walls. At a rear portion of the left well 11L, a second passenger seat 22 is arranged at the left side of the first passenger seat 21. Likewise, at a rear portion of the right well 11R, a third passenger seat 23 is arranged at the right side of the first passenger seat 21. Each of the second and third passenger seats 22 and 23 is arranged to enable seating of a single occupant with the rear partition wall 15 to the back. The third and second passenger seats 23 and 22 are arranged to enable sitting with legs closed inside the right and left wells 11R and 11L, respectively. Seat surfaces 22 a and 23 a of the third and second passenger seats 22 and 23 are lower than a seat surface 21 a of the first passenger seat 21 and higher than floor surfaces 11 a of the wells 11R and 11L.

At sides of the cockpit 3, the side walls 16R and 16L are arranged to gradually increase in right/left direction width toward the front from the third and second passenger seats 23 and 22. Thus, as the front side is approached, inner walls 17R and 17L of the side walls 16R and 16L bulge toward inner sides of the right and left wells 11R and 11L (in directions of approaching the tandem seat 12). The right and left wells 11R and 11L are thereby narrowed in right/left direction width. Consequently, the side walls 16R and 16L have wide width portions at portions corresponding to sides of the watercraft operator seat 13. Right and left storage portions 19R and 19L are provided in interiors of the side walls 16L and 16R at the wide width portions. The storage portions 19R and 19L are respectively provided with opening/closing lids 20R and 20L.

Anti-slip sheets 37 (indicated by crosshatching) may be arranged as necessary on the floor surfaces 11 a of the wells 11R and 11L.

The rear deck 4 is arranged to the rear of the rear partition wall 15 and has a rear water-access area 40 opened to a water surface at the rear of the hull 2, and a fourth passenger seat 24. The rear water-access area 40 includes a floor surface 40 a with a U-shape that is opened toward the front of the hull 2 in plan view. The floor surface 40 a is preferably sloped to descend gradually toward the rear of the hull 2, and a rear access gate 41 to the rear water surface is arranged at a stern center of the floor surface 40 a. Specifically, at the rear deck 4, the right and left side walls 16R and 16L decrease in height toward the rear and are interrupted at rear edges that oppose each other across the rear access gate 41. The water surface at the rear of the hull 2 can thereby be accessed from the rear access gate 41, and the hull 2 can be boarded from the water through the rear access gate 41.

The fourth passenger seat 24 is a seat enabling seating with the rear partition wall 15 to the back. The fourth passenger seat 24 is preferably arranged at a front side center of the rear water-access area 40 and is aligned with the tandem seat 12 along a center line C of the hull. The fourth passenger seat 24 is thus adjacent the first passenger seat 21 in the front/rear direction across the rear partition wall 15. A seat surface 24 a of the fourth passenger seat 24 preferably is higher than the floor surface 40 a of the rear deck 4, is lower than the seat surface 21 a of the first passenger seat 21, and approximately equal in height to the seat surfaces 22 a and 23 a of the second and third passengers seats 22 and 23. A passenger seated at the fourth passenger seat 24 can monitor a water area to the rear of the hull 2 or stick out a fishing rod to the rear of the hull 2, etc. That is, the passenger can perform various activities at the rear of the hull 2.

A pair of footrests 42R and 42L are provided respectively at rear edge portions of the side walls 16R and 16L, and the rear access gate 41 is disposed between these footrests. The right and left footrests 42R and 42L are formed by raising stern portions of the deck portion 2 b. The occupant seated at the fourth passenger seat 24 can place his/her feet on the right and left footrests 42R and 42L.

A seat portion of the fourth passenger seat 24 may be arranged to be detachable. In this case, a rear storage portion may be provided below the seat portion.

An occupant can move between the cockpit 3 and the rear deck 4, for example, by straddling over the rear partition wall 15 using the second or third passenger seat 22 or 23 as a step. Also, an occupant can move to the fourth passenger seat 24 from the first passenger seat 21 or move in an opposite direction by straddling over the rear partition wall 15.

At the right and left of the fourth passenger seat 24, the rear partition wall 15 has erect walls 15R and 15L at the rear deck 4 side. The erect walls 15R and 15L rise substantially vertically from a front edge of the floor surface 40 a of the rear deck 4. Thus, even if water enters into the rear deck 4, the water does not enter the cockpit 3.

Anti-slip sheets 44 (indicated by crosshatching) may be arranged as necessary on the floor surface 40 a of the rear water-access area 40, a surface of the access gate 41, and surfaces of the footrests 42R and 42L.

The towing tower 6 (omitted from illustration in FIG. 2 and FIG. 3) is arranged near a boundary portion between the cockpit 3 and the rear deck 4. The towing tower 6 is arranged to have an arch shape spanning across both side walls 16R and 16L and includes a pair of leg portions 61R and 61L and a towing plate 60. In plan view, the towing plate 60 preferably has a rectangular or substantially rectangular plate shape that is long to the right and left. A towing hook 62 is erected at substantially a center of an upper surface of the towing plate 60. In a periphery of the towing hook 62, the surface of the towing plate 60 is a sloping surface 63 that descends toward the rear. The leg portions 61R and 61L are respectively coupled to respective right and left edges of the towing plate 60.

Each of the leg portions 61R and 61L preferably has the form of a ladder that narrows in width toward the upper side. To be more specific, each of the leg portions 61R and 61L preferably includes a pair of stringers 65 and a plurality of rungs 66 spanned across the stringers 65 at equal intervals. Of the pair of stringers 65, the stringer 65 arranged at the front side has its base end portion fixed to the side wall 16R or 16L at a side of the cockpit 3 and an upper end portion there of is curved inward and coupled to a front portion of an edge of the towing plate 60. This front stringer 65 is curved so as to be directed toward the rear and thereafter be directed toward the front as the upper side is approached from the base end portion. Of the pair of stringers 65, the stringer 65 arranged at the rear side has its base end portion fixed to the side wall 16R or 16L at a side of the rear deck 4 and an upper end portion thereof is curved inward and coupled to a rear portion of an edge of the towing plate 60. This rear stringer 65 is curved so as to be directed toward the front as the upper side is approached from the base end portion. A holding cylinder 67, which is directed obliquely upward toward the rear, is coupled to the base end portion of each rear stringer 65. The holding cylinder 67 is arranged to enable insertion and holding of a base end portion of a fishing rod. The pair of stringers 65 are narrowed in mutual interval toward the upper end side. The stringers 65 are made, for example, of a metal material, and the rungs 66 are made of metal rods welded to the stringers 65.

As a whole, the leg portions 61R and 61L are curved toward the front as the upper side is approached. The towing plate 60 is thereby disposed substantially directly above the first passenger seat 21.

When a towing rope for water skiing, wakeboarding, etc., is to be coupled, an occupant climbs up either the leg portion 61R or 61L and hooks the towing rope onto the towing hook 62. During towing of a water skier or skim boarder, for example, the towing rope is in a tensioned state and is in a sloping state of descending toward the rear from the towing hook 62. The sloping surface 63 prevents or alleviates interference with the towing rope in the tensioned state.

Each of FIG. 6A, FIG. 6B, and FIG. 6C is an enlarged perspective view of an arrangement of the front deck 5.

The front deck 5 preferably has a planar shape that narrows in width toward a stem and has a front water-access area 50 that is opened to the front of the hull 2 at a stem portion. The front water-access area 50 is defined by right and left side wall portions 56R and 56L and the front partition walls 18R and 18L, and includes a front access gate 51, opened to the front, at a front end. The front water-access area 50 includes a floor surface 50 a with a substantially V-like shape that is opened to the rear of the hull 2 in plan view. The floor surface 50 a is sloped so as to descend toward the front of the hull 2, and the front access gate 51 for access to a front water surface is arranged at a stern portion center of the floor surface 50 a. The right and left side wall portions 56R and 56L are formed, for example, by raising right and left side edges of the front deck 5 to substantially the same heights as the front partition walls 18R and 18L. The side wall portions 56R and 56L are continuous with the front partition walls 18R and 18L, extend to the stem side, and are interrupted at front ends that oppose each other across the front access gate 51. The water surface in front of the hull 2 can thereby be accessed from the front access gate 51, and the hull 2 can be boarded from within the water through the front access gate 51.

The front partition walls 18R and 18L include erect walls 57R and 57L at the front deck 5 side. The erect walls 57R and 57L rise substantially vertically from a rear edge of the floor surface 50 a of the front deck 5. Thus, even if water enters into the front deck 4, the water does not enter the cockpit 3.

In front of the steering handle 30, a half-dome-like raised portion 52 that gradually rises obliquely upward toward the steering handle 30 is formed in a region surrounded by the substantially V-shaped floor surface 50 a. The handle holding portion 33 is attached to the raised portion 52.

The handle holding portion 33 is coupled to the raised portion 52 in a manner enabling opening and closing. More specifically, the handle holding portion 33 has a shape of a hood that is rotatable about a horizontal rotational axis extending in the right/left direction and arranged at a rear edge of the raised portion 52. A front portion of the handle holding portion 33 can thereby be raised to achieve a state shown in FIG. 6C. The steering handle 30 is fixed to a rear portion of the handle holding portion 33, and right and left rearview mirrors 34R and 34L are fixed near right and left side edges at the front relative to the steering handle 30. A seat attachment portion 53 that enables attachment and holding of a fifth passenger seat 25 is provided between the rearview mirrors 34R and 34L. FIG. 6A shows a state where the fifth passenger seat 25 is removed, and FIG. 6B shows a state where the fifth passenger seat 25 is attached to the seat attachment portion 53.

The seat attachment portion 25 may have a form of a cylindrical, recessed portion. As shown in FIG. 6C, the raised portion 52 is provided with a front storage portion 54 that can be opened and closed by the handle holding portion 33. That is, the front storage portion 54 is provided below the handle holding portion 33 in the closed state. The front storage portion 54 is arranged to enable storage of the fifth passenger seat 25.

The fifth passenger seat 25 includes a seat portion 25A and a shaft portion 25B fixed to a lower surface of the seat portion 25A. The shaft portion 25B is arranged so that it can be fitted into the seat attachment portion 53 and held by the seat attachment portion 53. The fifth passenger seat 25 is thus arranged to be attachable and detachable with respect to the seat attachment portion 25.

The fifth passenger seat 25 is a seat, which, when attached to the seat attachment portion 53, enables sitting with the steering handle 30 to the back. The fifth passenger seat 25 may be arranged to be rotatable about the shaft portion 25B. A seat surface 25 a of the fifth passenger seat 25 is higher than the seat surface of the watercraft operator seat 13 and, for example, is further higher than the steering handle 30. An occupant seated on the fifth passenger seat 25 can monitor a water area in front the hull 2 or stick out a fishing rod to the front of the hull 2, etc. That is, the occupant can perform various activities at the front of the hull 2.

Inner wall surfaces of the side wall portions 56R and 56L define sloping surfaces that gradually rise obliquely upward from the floor surface 50 a to the exterior. The inner wall surfaces of the side wall portions 56L and 56R provide a pair of footrests 55R and 55L. The occupant seated at the fifth passenger seat 25 can place his/her feet on the right and left footrests 55R and 55L.

Anti-slip sheets 58 (indicated by crosshatching) may be disposed as necessary on the floor surface 50 a of the front water-access area 50, a surface of a front access gate 51, and surfaces of the footrests 42R and 42L.

FIG. 7 is a schematic side view of an arrangement of an interior of the hull 2 of the water jet propulsion watercraft 1. Also, FIG. 8 is a schematic plan view of the arrangement of the interior of the hull 2.

An internal space of the hull 2 is partitioned in the front/rear direction by a plurality of partition walls (bulkheads) 70 to 73, is partitioned in the right/left direction by a plurality of partition walls 74 to 78, and is partitioned in the up/down direction by a plurality of partition walls 79. A fuel tank chamber 81 and an engine chamber 82 are thereby provided below the tandem seat 12. Further, a big-size storage chamber 83 is provided in front of the fuel tank chamber 81, and storage chambers 84 are provided at sides of the fuel tank chamber 81. Also, battery chambers 85 are provided at sides of the engine chamber 82. Floatation chambers 86, 87, and 88 arranged to house floating bodies are respectively provided in front and at sides of the big-size storage chamber 83 and at the rear of the battery chambers 85. Further, a jet unit chamber 90 is provided to the rear of the engine chamber 82, and water lock chambers 89 are provided between the jet unit chamber 90 and the floatation chambers 88. A storage chamber 80, which can be accessed for example by removing a seat portion of the fourth passenger seat 24, is arranged above the jet unit chamber 90.

A fuel tank 91 is arranged inside the fuel tank chamber 81. The fuel tank 91 is arranged below the watercraft operator seat 13 and has a fueling port 91 a at an upper side. A user can access the fueling port 91 a, for example, by removing the tandem seat 12 and replenish fuel into the fuel tank 91.

An engine 95 is housed and fixed in the engine chamber 82. The engine chamber 82 is arranged substantially immediately below the first passenger seat 21. Batteries 96, for supplying electrical power to electrical components of the engine 95 and other electrical components installed in the hull 2, are housed in the battery chambers 85. A water lock 97 interposed in a middle of an exhaust passage of the engine 95 is housed in each water lock chamber 89. The water lock 97 is a sealed container and is connected to an exhaust pipe 98 from the engine 95 and an underwater exhaust pipe 99. Exhaust from the engine 95 is introduced into the water lock 97 from the exhaust pipe 98 and is further passed through the underwater exhaust pipe 99 and discharged into the water in the vicinity of the stern of the hull 22. The water lock 97 prevents water entering through the underwater exhaust pipe 99 from entering into the exhaust pipe 98 side.

A jet propulsion device 100 is arranged in the jet unit chamber 90. The jet propulsion device 100 is driven by a driving force of the engine 95 and is arranged to take in water in the surroundings of the hull 2 from a hull bottom portion and jet the water rearward from a jetting port 101.

FIG. 9 is a schematic sectional view for explaining an arrangement example of the jet propulsion device 100. The jet propulsion device 100 includes a driveshaft 103, an impeller 104, a deflector 105, and a reverse bucket 106 (omitted from illustration in FIG. 1 to FIG. 8). A crankshaft 110 (or a transmitting shaft coupled to a crankshaft) protrudes from a rear portion of the engine 95, and a coupling member 111 is attached to a rear end of the crankshaft 110. The driveshaft 103 is arranged so as to extend rearward at the rear of the coupling member 111. The driveshaft 103 is supported by a bearing 112 that is attached to the partition wall 73 of the hull 2. The bearing 112 is covered by a seal member 113 which is arranged to minimize inflow of water into the engine chamber 82.

An impeller 104 is attached to a rear portion of the driveshaft 103. The impeller 104 is fixed to the driveshaft 103 and is arranged to rotate together with the driveshaft 103. The impeller 104 is disposed in a water passage portion 121 formed at a rear lower portion of the hull 2 and is arranged to pump up water from a water intake portion 123 of a hull bottom 122 and jet water from a water discharge portion 124 (nozzle) at the rear portion of the hull 2.

A deflector 105 that controls the jetting direction of water and converts it to the right and left is attached to the water discharge portion 124. The deflector 105 is arranged to be rotatable to the right and left directions about a shaft portion 125 in linkage with the steering handle 30 (see FIG. 1). Water is jetted to the rear of the hull 2 from the jetting port 101 of the deflector 105.

The reverse bucket 106 that is arranged to forwardly invert the direction of water jetted from the water discharge portion 124 during reverse drive is attached to the water discharge portion 124. The reverse bucket 106 is arranged to be rotatable in the up and down directions about a shaft portion 126. The reverse bucket 106 is arranged to be disposed at an upwardly sprung position (indicated by solid lines) during forward drive and be disposed at a position (indicated by phantom lines) to the rear of the water discharge portion 124 during reverse drive.

The water discharge portion 124, the deflector 105, and the reverse bucket 106 are arranged in a pump chamber 107. The pump chamber 107 is preferably provided by recessing a vicinity of a lower rear edge of the hull body 2 a of the hull 2 preferably in a rectangular parallelepiped shape. The water discharge portion 124, the deflector 105, and the reverse bucket 106 are thus disposed in the water below the rear portion of the hull 2.

The engine 95 is an internal combustion engine and includes a cylinder body 131, a cylinder head 132, a cylinder head cover 133, and a crankcase 134 housing the crankshaft 110. Pistons 135 are slidably arranged at an inner peripheral surface of the cylinder body 131. An upper end portion of a connecting rod 136 is rotatably attached to each piston 135. The cylinder head 132 is arranged so as to close an opening at one side of the cylinder body 131. An intake valve 137 and an exhaust valve (not shown) are arranged in the cylinder head 132. Further, a cam that moves the intake valve 137 and the exhaust valve (not shown) at a predetermined timing and a camshaft that rotates the cam (both of which are omitted from illustration) are arranged in the cylinder head 132.

Spark plugs 138 are provided in the cylinder head 132. A tip portion of each spark plug 138 is arranged so as to protrude inside a combustion chamber 139 defined by the cylinder body 131, the cylinder head 132, and the piston 135.

The cylinder body 131 is attached to the crankcase 134. The crankshaft 110 is supported in a state of being sandwiched between the cylinder body 131 and the crankcase 134. The crankshaft 110 is attached to the crankcase 134 and the cylinder body 131 so as to extend in the front/rear direction.

A lower end portion of each connecting rod 136 is rotatably attached to the crankshaft 110. The crankshaft 110 is thereby arranged to be rotated in accompaniment with the sliding of the pistons 135 up and down.

As described above, with the water jet propulsion watercraft 1 according to the present preferred embodiment, the entire periphery of the cockpit 3 is surrounded by wall surfaces, and the water in the surroundings of the hull 2 thus does not enter readily. That is, the interior of the cockpit 3 is a dry area and an occupant inside the cockpit 3 can avoid getting wet with water. Meanwhile, the rear deck 4 has the rear water-access area 40 that is open to the rear, and the front deck 5 has the front water-access area 50 that is open to the front. The floor surface 40 a of the rear water-access area 40 has the slope that descends towards the rear, and the floor surface 50 a of the front water-access area 50 has the slope that descends towards the front. Water that enters into the water-access areas 40 and 50 are thus guided by the floor surfaces 40 a and 50 a and drained rapidly from the access gates 41 and 51. An occupant wishing to enjoy swimming can enter the surrounding water or board onto the hull 2 from the water via the water-access area 40 or 50. Needs of both occupants who do not wish to get wet with water and occupants desiring access into water can thereby be met at the same time.

Moreover, the tandem seat 12, which is a saddle type seat, is disposed at the cockpit 3, and the engine 95 is disposed in the space below the tandem seat 12. The hull 2 can thus be made short in total length because the engine does not have to be arranged to the rear relative to the cockpit 3. For example, the hull 2 can be made approximately 4 or 5 meters in total length and be made approximately 2 meters in total width. The hull 2 can thus be arranged compactly.

The water jet propulsion watercraft 1 thus belongs to a new category that differs from both conventional personal watercrafts and jet boats. That is, the water jet propulsion watercraft 1 has an arrangement enabling the dry area (the cockpit 3) and the water-access areas 40 and 50 to both be provided in combination in the compact hull 2 and can thus be used casually and is yet applicable to diverse needs of the occupants.

Also, with the water jet propulsion watercraft 1 according to the present preferred embodiment, the interior of the cockpit 3 is divided into the two regions 3R and 3L (wells 11R and 11L) at the right and left by the tandem seat 12. The tandem seat 12 can thereby be disposed at the center, and balance to the right and left of the hull 2 can be achieved readily. The right and left regions 3R and 3L are accommodation spaces for the occupants, and enable fishing and other activities to be performed at the right and left of the hull 2. Fishing and other activities are also enabled at the front and rear water-access areas 40 and 50 of the hull 2, and the occupants on the hull 2 can thus perform fishing and other activities in the four directions of front, rear, right, and left.

Also, the tandem seat 12 includes the watercraft operator seat 13 at the front and the first passenger seat 21 at the rear. The first passenger seat 21 enables seating of up to two persons. The second and third passenger seats 22 and 23 are provided at the right and left of the first passenger seat 21. Up to five occupants can thus be accommodated within the cockpit 3. When the watercraft is boarded by one person, the occupant sits at the watercraft operator seat 13. The watercraft operator seat 13 is arranged at the center of the hull 2 and thus the hull 2 is well balanced. When two persons board the watercraft, one sits at the watercraft operator seat 13 and the other sits at the first passenger seat 21. The hull 2 is well balanced in this case as well because the tandem seat 12 is arranged at the center of the hull 2. When three persons board the watercraft, one sits at the watercraft operator seat 13 and the other two can sit at the first passenger seat 21. Or one person may sit at the watercraft operator seat 13 and the other two may sit at the second and third passenger seats 22 and 23. In either case, the hull 2 can be balanced in weight symmetrically to the right and left. When four persons board the watercraft, the hull 2 can be balanced to the right and left by one person sitting at the watercraft operator seat 13, one person sitting at the first passenger seat 21, and the remaining two persons sitting at the second and third passenger seats 22 and 23, respectively. When five persons board the watercraft, one person sits at the watercraft operator seat 13, two persons sit at the first passenger seat 21, and the remaining two persons sit at the second and third passenger seats 22 and 23, respectively. Balance to the right and left can thereby be achieved. Symmetrical weight balance to the right and left can thus be achieved substantially inside the cockpit 3 for boarding of any number of persons from one to five.

Further, the engine 95 is preferably arranged below the first passenger seat 21, and the third and second passenger seats 23 and 22 are disposed at the right and left of the first passenger seat 21. A center of gravity of the entirety of the hull 2, including the occupants, can thereby be disposed in a vicinity of the engine 95. Consequently, shortening of the total length of the hull 2 by arrangement of the engine 95 in the space below the first passenger seat 21 can be achieved while at the same time disposing the center of gravity at the rear. By the rearward disposing of the center of gravity, a contribution can be made toward establishing motion performance (in particular, turning performance) of the hull 2.

Also, in the preferred embodiment, the fourth passenger seat 24 is provided at the rear deck 4, and an occupant can thus sit at the fourth passenger seat 24 and monitor the water surface to the rear or perform fishing, etc. The rear deck 4 has the rear water-access area 40 that is opened to the rear, and thus when the water jet propulsion watercraft 1 undergoes high-speed travel, a seat inside the cockpit 3 is suitably used. The fourth passenger seat 24 is mainly used suitably during mooring and low speed movement (for example, during trolling).

Yet further, the fourth passenger seat 24 is adjacent the first passenger seat 21 across the rear partition wall 15 at the rear of the first passenger seat 21. Concentrating of the center of gravity at the vicinity of the engine 95 can thereby be achieved and thus a contribution can be made to establishing the motion performance of the hull 2.

Also, the fourth passenger seat 24 faces the rear of the hull 2, and thus an occupant seated at the fourth passenger seat 24 can stick out a fishing rod toward the rear.

Further, the rear deck 4 includes footrests 55R and 55L arranged to enable an occupant, seated at the fourth passenger seat 24, to place his/her feet thereon. The occupant at the fourth passenger seat 24 can place his/her feet on the footrests 55R and 55L for comfort.

Also, with the present preferred embodiment, convenience for the occupants is promoted by the storage portions 19R and 19L being provided at the right and left side walls 16R and 16L. In addition, the regions 3R and 3L at the right and left of the tandem seat 12 are narrowed. Movement ranges of the occupants can thereby be restricted appropriately to achieve stabilization of the hull 2.

Further, with the present preferred embodiment, the fifth passenger seat 25 is preferably provided at the front deck 5, and thus fishing and other activities can be performed readily with respect to the front of the hull 2. The front deck 5 is mainly used suitably during mooring and low speed movement (for example, during trolling) because it has the front water-access area 50 that is opened to the front, and a seat within the cockpit 3 is suitably used during high-speed travel. As shown most clearly in FIG. 2, the fifth passenger seat 25 is arranged such that the center line C of the hull 2 passes therethrough in plan view. The fifth passenger seat 25 can thereby be arranged without compromising the balance of the hull 2.

Further, with the present preferred embodiment, the fifth passenger seat 25 can be attached to and detached from the seat attachment portion 53 provided at the front deck 5 and the fifth passenger seat 25 can be removed when it is unnecessary. For example, when the water jet propulsion watercraft 1 is made to travel at high speed, the fifth passenger seat 25 is preferably removed to reduce air resistance and further secure a wide field of view for a watercraft operator. Also, when fishing or other activity is to be performed or during low speed travel (for example, during trolling), the fifth passenger seat 25 is preferably attached to the seat attachment portion 53 to facilitate the activity at the front deck 5. Moreover, in the present preferred embodiment, the front storage portion 54 capable of storing the fifth passenger seat 25 is provided at the front deck 5. Transport of the fifth passenger seat 25 is thereby facilitated.

Further, with the present preferred embodiment, the side wall portions 56R and 56L are formed by raising the hull edge portions of the front deck 5 and the footrests 55R and 55L are formed from the sloping wall surfaces at the inner sides. An occupant seated at the fifth passenger seat 25 can thus place his/her feet on the footrests 55R and 55L for comfort.

Also, with the present preferred embodiment, the arch-shaped towing tower 6 is provided, and towing can be performed using the towing tower 6. Specifically, a rope for towing a water skier, etc., can be coupled to the towing tower 6. The towing tower 6 is formed to the arch shape having the leg portions erected on the right and left side walls 16R and 16L and can thus be arranged without compromising occupant comfort of the cockpit 3 and the rear deck 4. Also, the towing tower 6 is arranged near the boundary portion between the cockpit 3 and the rear deck 4 and thus contributes to rearward disposing of the center of gravity of the hull 2. A contribution can thus be made to establishing the motion performance of the hull 2.

Although preferred embodiments of the present invention have been described above, the present invention can be put into practice in other modes as well. For example, although the water jet propulsion watercraft 1 according to the above-described preferred embodiment preferably includes not only the deck at the rear portion of the hull 2 but the front deck 5 at the front portion as well, the front deck 5 may be omitted. Also, although with the above-described preferred embodiment, the detachable fifth passenger seat 25 is preferably provided at the front deck 5, the fifth passenger seat 25 may be omitted. Also, the fifth passenger seat 25 may be fixed to the front deck 5 in a manner such that the field of view of the watercraft operator can be secured.

Also, although with the above-described preferred embodiment, the fourth passenger seat 24 is preferably provided at the rear deck 4, the fourth passenger seat 24 may be omitted.

Although with the above-described preferred embodiments, an arrangement preferably including the towing tower 6 has been described, the towing tower 6 may be omitted.

While preferred embodiments of the present invention have been described above, it is to be understood that variations and modifications will be apparent to those skilled in the art without departing the scope and spirit of the present invention. The scope of the present invention, therefore, is to be determined solely by the following claims.

The present application corresponds to Japanese Patent Application No. 2009-242654 filed in the Japan Patent Office on Oct. 21, 2009, and the entire disclosure of the application is incorporated herein by reference. 

1. A water jet propulsion watercraft comprising: a hull; a cockpit arranged at a hull center and including a periphery surrounded by a wall surface; a rear deck arranged at a hull rear portion to a rear of the cockpit and including a rear water-access area that is open to a rear of the hull; a saddle type watercraft operator seat arranged in the cockpit; a jet propulsion device attached to the hull and arranged to apply a propulsive force to the hull by sucking in water from surroundings and jetting the water; and an engine attached to the hull and arranged to apply a driving force to the jet propulsion device.
 2. The water jet propulsion watercraft according to claim 1, wherein the saddle type watercraft operator seat extends in a front/rear direction of the hull and divides an interior of the cockpit into two regions at right and left.
 3. The water jet propulsion watercraft according to claim 1, further comprising a first passenger seat arranged inside the cockpit and at a rear of the saddle type watercraft operator seat, wherein the engine is arranged below the first passenger seat.
 4. The water jet propulsion watercraft according to claim 3, further comprising: a second passenger seat arranged inside the cockpit and at a right side of the first passenger seat; and a third passenger seat arranged inside the cockpit and at a left side of the first passenger seat.
 5. The water jet propulsion watercraft according to claim 1, further comprising another passenger seat provided at the rear deck.
 6. The water jet propulsion watercraft according to claim 1, wherein the cockpit is defined by right and left side walls, storage spaces are provided in the right and left side walls, and spaces to right and left of the saddle type watercraft operator seat are narrowed by the storage spaces.
 7. The water jet propulsion watercraft according to claim 1, further comprising a front deck arranged at a hull front portion in front of the cockpit and having a front water-access area that is opened to a front of the hull.
 8. The water jet propulsion watercraft according to claim 7, further comprising another passenger seat arranged at the front deck.
 9. The water jet propulsion watercraft according to claim 7, further comprising a seat attachment portion arranged at the front deck and arranged to enable attachment and detachment of another passenger seat.
 10. The water jet propulsion watercraft according to claim 7, further comprising a storage portion disposed at the front deck and arranged to be capable of housing another passenger seat that is attachable to the seat attachment portion.
 11. The water jet propulsion watercraft according to claim 7, further comprising another passenger seat arranged at the front deck, and a footrest arranged to accommodate feet of a passenger seated at the another passenger seat and including a shape that rises from a hull edge portion at the front deck.
 12. The water jet propulsion watercraft according to claim 6, wherein the front deck includes a floor surface that is sloped so as to descend toward the front.
 13. The water jet propulsion watercraft according to claim 1, further comprising an arch-shaped towing tower erected from right and left edge portions of the hull near a boundary portion between the cockpit and the rear deck. 